Proponents of Question 1 on Portland’s municipal ballot Tuesday have created an impression that the city’s public spaces are under perpetual threat.

To blunt it, they want to set a high threshold of support when it comes to transactions involving the city’s public spaces. But they would set the bar so high that any related decision-making would be made unwieldy.

There’s no compelling reason for the changes they seek, and those changes could preclude thoughtful, long-range, land-use planning in Maine’s largest city. We urge Portland residents to vote no on Question 1.

Question 1 draws five dozen of Portland’s parks, plazas and other open spaces into the mix. But the ballot measure at its core is a check on the City Council’s decision last September, in a 6-3 vote, to sell two-thirds of Congress Square Plaza — which is less than half an acre — to Rockbridge Capital for $524,000.

The Ohio-based developer that renovated the adjacent Westin Portland Harborview Hotel plans a one-story event center on the space. A third of it would remain public space. But with the referendum pending, the sale is on hold.

A “yes” vote would add 35 public spaces — including Congress Square — to a class of city properties that receive special protection through the city’s Land Bank Commission. Under the ordinance a “yes” vote would enact, any sale of one of the 60 designated public spaces would have to draw support from at least eight of nine city councilors. A voter referendum on the sale would follow if the sale garnered less council support.

A “yes” vote would also nullify the council’s 6-3 Congress Square sale vote, likely forcing a referendum on the question.

The Question 1 ordinance would effectively designate decisions on land-use changes as more important than any other policy decision the Portland City Council has to make.

No other policy change vetted by the City Council requires more than a simple majority of votes to pass. And there’s no evident reason to place a lopsided emphasis on land-use decisions: There has been no pattern of the city’s public spaces being usurped. According to the city, more than 200 acres have been added to the city’s public space portfolio in the last quarter century.

The referendum requirements for land sales could also impede thoughtful, comprehensive, long-range planning by the city. Planning is a complex, multistep process that requires long-term vision and can’t be simplified to a “yes” or “no” question. Indeed, it’s a process that can be easily undermined if reduced to such simplified terms.

Plus, even without the proposed new rules, Portland residents have more opportunities to influence the outcome of the pending Congress Square sale and development.

The sale has yet to go through, and Rockbridge Capital will have to subject its plans to full design, permitting and zoning reviews — all public processes in which the city will have significant leverage to exact terms that it wants. The plans will ultimately be subject to council approval, according to city spokeswoman Jessica Grondin.

A “yes” vote would give in to a campaign without proven reasons and make a part of city government unwieldy when existing rules offer residents several opportunities to influence decision-makers. If residents detest the votes cast by councilors, they can throw them out in the next election — an appropriate use of their voting power.